This may be attributed to the seasonal intrusion of the Kuroshio Current to the study water.Nitrogen was a better tracer than carbon in investigating trophic relationships of marine organisms.

• 生物体内同位素含量的季节性差异表现在体 型较小的浮游生物内，春、夏差异不明显而分别与秋季有显著差异，可能与黑潮的季节 性消长有关。